Consumer products involving vacuuming and sealing plastic bags have grown in popularity over the years. The basic model available includes a seal wire which seals the length of the bag and a vacuum pump which pumps air out of the bag prior to sealing. This model works well enough to have sold and inspired imitation.
Unfortunately, the model described requires use of expensive components and still suffers from air bubbles in some vacuum-sealed packages. In particular, the seal wire used to seal the plastic is heated throughout its entire length at one time, requiring a high current for activation, and a correspondingly big and expensive transformer. Moreover, the larger the area to be heated, the longer the heating process is likely to take. Similarly, the vacuum must be maintained over a wide physical area (the length of the bag) and may increase the time needed to seal due to any cold air flowing over the area to be sealed.
Transformers in particular are well-known as expensive components, and their cost increases in a nonlinear fashion, such that a first transformer with twice the capacity of a second transformer may cost much more than twice the price of the second transformer. Similarly, the bigger the cross-section through which vacuum must be maintained, the larger (and more costly) the pump must be to maintain that vacuum.
Accordingly, it may be preferable to implement a system in which relatively low-cost components may be used to ease the requirements for a large transformer and a large vacuum pump.